Though tigers are ______ to people, they are ______ now and we should protect them or they will die out.

A．dangerous ; dangerous

B．in danger ; in danger

C．dangerous ; in danger

D．in danger ; dangerous

“反间计”策略运用时的注意点包括（）

A、方法

B、利用时效

C、效果

D、善于搬弄